Not long ago i watched my coworker disassembling a personal computer using only one tool. Was it the right tool for the job? Yes and no. It was the tool he had… it worked, however, there is definitely more than one tool out there that would have made the job easier! This example is certainly one that many fiber optic installers know all too well. As being a gentle reminder, how many of you have used your Splicer’s Tool Kit (cable knife/scissors) to remove jacketing or even slit a buffer tube and then make use of the scissors to hack away at the Kevlar? Did you nick the glass? Did you accidentally cut through the glass and have to start over?
Correctly splicing and terminating Fiber Coloring Machine requires special tools and methods. Training is very important and there are lots of excellent types of training available. Tend not to mix your electrical tools with your fiber tools. Use the right tool for the task! Being experienced in fiber work will become increasingly necessary as the value of data transmission speeds, fiber for the home and fiber for the premise deployments still increase.
Many factors set fiber installations besides traditional electrical projects. Fiber optic glass is extremely fragile; it’s nominal outside diameter is 125um. The slightest scratch, mark or even speck of dirt will change the transmission of light, degrading the signal. Safety factors are important simply because you will work with glass that can sliver into your skin without getting seen through the eye. Transmission grade lasers are incredibly dangerous, and require that protective eyewear is a must. This industry has primarily been dealing with voice and data grade circuits that could tolerate some interruption or slow down of signal. Anyone speaking would repeat themselves, or even the data would retransmit. Today we are working with IPTV signals and customers that will not tolerate pixelization, or momentary locking in the picture. All the situations mentioned are cause of the consumer to look for another carrier. Each situation might have been avoided if proper attention was given to the techniques used while preparing, installing, and maintaining fiber optic cables.
Having said that, why don’t we review basic fiber preparation? Jacket Strippers are utilized to eliminate the 1.6 – 3.0mm PVC outer jacket on simplex and duplex fiber cables. Serrated Kevlar Cutters will cut and trim the kevlar strength member directly beneath the jacket and Buffer Strippers will take away the acrylate (buffer) coating from the bare glass. A protective plastic coating is used for the bare fiber after the drawing process, but just before spooling. The most typical coating is actually a UV-cured acrylate, which can be applied by two layers, resulting in a nominal outside diameter of 250um for the coated fiber. The coating is highly engineered, providing protection against physical damage due to environmental elements, like temperature and humidity extremes, exposure to chemicals, point of stress… etc. while minimizing optical loss. Without one, the producer would struggle to spool the fiber without breaking it. The 250um-coated fiber will be the building block for most common fiber optic cable constructions. It is often used as is, especially when additional mechanical or environmental protection is not required, including on the inside of optical devices or splice closures. For additional physical protection and ease of handling, a secondary coating of polyvinyl chloride (PVC) or Hytrel (a thermoplastic elastomer that has desirable characteristics for use as a secondary buffer) is extruded over the 250um-coated fiber, enhancing the outside diameter up to 900um. This sort of construction is called ‘tight buffered fiber’. Tight Buffered may be single or multi fiber and they are observed in Premise Networks and indoor applications. Multi-fiber, tight-buffered cables often can be used for intra-building, risers, general building and plenum applications.
‘Loose tube fiber’ usually includes a bundle of fibers enclosed in a thermoplastic tube referred to as a buffer tube, which has an inner diameter that is slightly greater than the diameter from the fiber. Loose tube fiber has a space for your fibers to grow. In certain climatic conditions, a fiber may expand and after that shrink repeatedly or it may be exposed to water. Fiber Cables will sometimes have ‘gel’ in this particular cavity (or space) yet others which are labeled ‘dry block’. You can find many loose tube fibers in Outside Plant Environments. The modular style of Fiber Coloring Machine typically holds as much as 12 fibers per buffer tube using a maximum per cable fiber count in excess of 200 fibers. Loose-tube cables can be all-dielectric or optionally armored. The armoring can be used to guard the cable from rodents including squirrels or beavers, or from protruding rocks in a buried environment. The modular buffer-tube design also permits easy drop-off of groups of fibers at intermediate points, without disturbing other protected buffer tubes being routed to many other locations. The loose-tube design will help with the identification and administration of fibers in the system. When protective gel is present, a gel-cleaner including D-Gel is going to be needed. Each fiber is going to be cleaned with all the gel cleaner and 99% alcohol. Clean room wipers (Kim Wipes) are a wonderful decision to use with all the cleaning agent. The fibers within a loose tube gel filled cable normally have a 250um coating therefore they are definitely more fragile compared to a tight-buffered fiber. Standard industry color-coding is additionally utilized to identify the buffers as well because the fibers in the buffers.
A ‘Rotary Tool’ or ‘Cable Slitter’ can be utilized to slit a ring around and through the outer jacketing of ‘loose tube fiber’. As soon as you expose the durable inner buffer tube, you can use a ‘Universal Fiber Access Tool’ which is perfect for single central buffer tube entry. Used on the same principle because the Mid Span Access Tool, (which allows accessibility multicolored buffer coated tight buffered fibers) dual blades will slit the tube lengthwise, exposing the buffer coated fibers. Fiber handling tools for instance a spatula or perhaps a pick will help the installer to gain access to the fiber in need of testing or repair. When the damaged fiber is exposed a hand- stripping tool will be employed to remove the 250um coating in order to work with the bare fiber. The next step will be washing the fiber end and preparing so that it is cleaved. A good cleave is probably the most significant factors of producing a low loss on the splice or a termination. A Fiber Optic Cleaver is a multipurpose tool that measures distance through the end in the buffer coating towards the point where it will likely be joined and it precisely cuts the glass. Always remember to employ a fiber trash-can for that scraps of glass cleaved off the fiber cable.
When performing fusion splicing you might need a Fusion Splicer, fusion splice protection sleeves, and isopropyl alcohol and stripping tools. If you use a mechanical splice, you will require stripping tools, mechanical splices, isopropyl alcohol and a mechanical splice assembly tool. When hand terminating a fiber you will want 99% isopropyl alcohol, epoxy/adhesive, a syringe and needle, polishing (lapping) film, a polishing pad, a polishing puck, a crimp tool, stripping tools, fiber optic connectors ( or splice on connectors) and piano wire.
Each time a termination is finished you need to inspect the conclusion face in the connector with Optical Fiber Ribbon Machine. Ensuring that light is becoming through either the splice or the connection, a Visual Fault Locator can be used. This device will shoot a visible laser down the fiber cable so that you can tell that we now have no breaks or faulty splices. In the event the rhnnol light stops down the fiber somewhere, there is probably a break in the glass at that point. If you have more than a dull light showing on the connector point, the termination was not successful. The light must also pass through the fusion splice, when it does not, stop and re- splice or re-terminate.